If you upload content from multiple sources, or re-upload/repurpose someone else’s content then you won’t be eligible for YPP. Check out the FAQs and best practices here: https://yt.be/help/reused-content … and you can always reapply in 30 days.
We look at channel activity–things like uploaded videos, strikes, views, subs, and watch time—to ensure it meets our guidelines and monetization policies. Resources are available on your Monetization tab and note that you can reapply to the program in 30 days.